Joe - the chain is rarely, if at all, on the smallest cog next to the chain stay. It is normally in either cog 4 or 5, counting from the largest cog outward. I can remember when a company by the name of Sedis (Sedisport?) first introduced a narrower chain back in the late 70's in order to squeeze more gears onto a freewheel with normal 120-126mm rear dropout spacing. In my opinion, it's been downhill ever since with manufacturers trying to outdo one another with wider and wider dropout spacing and 9+ cogs. OTOH, I have an old '71/'72 Fuji Finest on which I'm running a 5-speed freewheel on a 120mm PW hub, friction shifted, and everything works just fine all the time.
On Monday, May 30, 2022 at 8:36:40 PM UTC-5 Joe Bernard wrote: > Huh, I'm stumped. It crunches under hard pedaling and this time the chain > snapped, which sounds like the chain wanted to keep going and something > back there didn't want to budge. How's the clearance between small cog and > chainstay? This is my last shot at a wild guess..maybe under heavy power > the cassette is contacting the frame at the dropout. > > On Monday, May 30, 2022 at 6:16:12 PM UTC-7 George Schick wrote: > >> Joe - I thought about that and have since replaced the chain, but in all >> likely hood the cassette should still be OK. It's not the original with >> the bike; I replaced the one with which the bike shipped with another (same >> manf.) that has slightly different gearing. The previous cassette had the >> same problems. >> >> >> On Monday, May 30, 2022 at 8:09:00 PM UTC-5 Joe Bernard wrote: >> >>> It could be anything but what I think we know now is the chain is busted >>> and chain and cassette are both probably pretty old. Based on my >>> supposition - pulled out of thin air - that your chain never mated well >>> with that cassette I would replace both now and see what happens. >>> >>> Joe Bernard >>> >>> On Monday, May 30, 2022 at 12:23:13 PM UTC-7 George Schick wrote: >>> >>>> Bill - thanks for the quick response. Bill asks... >>>> >>>> *(have you been) riding the same SRAM 971 chain for 18 years, and you >>>> actually ride the bike a decent amount, (if so) your entire drivetrain is >>>> likely toast. Is that what's going on? Or, do you replace your chain >>>> frequently, and the noise never changes?* >>>> >>>> I can't recall whether I've had that same chain in use on that bike for >>>> 18 years. I regularly clean and lube it and check the chain wear with a >>>> Park chain gauge. >>>> >>>> *Have you tried riding your bike with different pedals?* >>>> >>>> Yes, and it has still occurred over the years. >>>> >>>> *Have you tried riding your bike with a different rear wheel?* >>>> >>>> No, this bike has always had that same rear wheel, a Shimano Dura Ace >>>> hub, a Velocity OC rim, and Wheelsmith spokes. I've removed, cleaned, and >>>> re-lubed the rear axle several times over the years and I've never noticed >>>> any uneven wear on the bearing races. >>>> >>>> *Is the noise the same regardless of which front chainring you are in?* >>>> >>>> The crank has a Velo Orange Cru with 48/34 chainrings. It originally >>>> had a TA Syrius crankset with similar chainring sizes and it did the same >>>> thing then. Because of the relatively flat terrain in NE Illinois I ride >>>> in the larger 48 tooth chainring 95% of the time. The small chainring is >>>> only used for longer steep climbs such as ones up from river bottoms to >>>> ridges at the top. >>>> >>>> *Have you pulled the crank arms of and checked the BB bearings?* >>>> >>>> The BB on this bike now is a Phil Wood and it has never given any >>>> indication of a problem. I have pulled the crank arms of, as you say, on >>>> occasion when I noticed a different kind of clunking noise (though >>>> quieter) >>>> and found that the fixing rings were loose. I took care of that problem >>>> with LocTite and it has not occurred since. The original BB was an Axxis >>>> and the clunking noise was present even then. >>>> >>>> *Sometimes, a headset problem can feel like drive train noise.* >>>> >>>> The headset on this bike had indeed indexed a number of years ago, but >>>> I swapped it for an IRC roller drive and it's been fine ever since. >>>> >>>> *If you don't want to dive into iterative and time-consuming >>>> diagnostics, have a mechanic you trust look into it,* >>>> >>>> Don't know of one in the area. Mostly just guess-work types who try to >>>> swap this out for that, sometimes with success and other times not.. >>>> >>>> Nevertheless, thanks for your diagnostic suggestions, Bill. Are you in >>>> SE Michigan these days or back in NoCal? >>>> >>>> >>>> On Monday, May 30, 2022 at 1:51:10 PM UTC-5 Bill Lindsay wrote: >>>> >>>>> George indicates that he's had a loud clunking or crunching sound >>>>> coming from his bike for 18 years under hard pedaling. He asks "what the >>>>> heck gives?" >>>>> >>>>> Have you tried to address it in any way? What have you tried? >>>>> >>>>> Generally these "my bike makes sounds I don't like under hard >>>>> pedaling" involve changing one thing at a time and using the changes in >>>>> the >>>>> sound to narrow down the source. If you've been riding the same SRAM 971 >>>>> chain for 18 years, and you actually ride the bike a decent amount, then >>>>> your entire drivetrain is likely toast. Is that what's going on? Or, do >>>>> you replace your chain frequently, and the noise never changes? If >>>>> that's >>>>> the case, then you've likely ruled out the chain itself as the source. >>>>> >>>>> Have you tried riding your bike with different pedals? If the noise >>>>> is the same with different pedals, then it's probably not the pedals. >>>>> Have you tried riding your bike with a different rear wheel? If the >>>>> noise is the same with a different rear wheel, then the rear wheel is >>>>> probably not the source. >>>>> >>>>> Is the noise the same regardless of which front chainring you are in? >>>>> If so, then one chainring is probably not the source. >>>>> >>>>> Have you pulled the crank arms of and checked the BB bearings? >>>>> >>>>> Sometimes, a headset problem can feel like drive train noise. >>>>> >>>>> If you don't want to dive into iterative and time-consuming >>>>> diagnostics, have a mechanic you trust look into it, >>>>> >>>>> Bill Lindsay >>>>> El Cerrito, CA >>>>> >>>>> >>>>> >>>>> On Monday, May 30, 2022 at 11:23:20 AM UTC-7 George Schick wrote: >>>>> >>>>>> Ever since I've owned my Ram I've had a unique, loud clunking or >>>>>> crunching sound coming from the drive train, especially when I started >>>>>> from >>>>>> a standing stop or occasionally when hammering up an incline. I used to >>>>>> associate it with the "ghost shifting" phenomenon as posters here >>>>>> referred >>>>>> to certain chain and cassette indexed shift combinations. But this loud >>>>>> "clunking" sound never resulted in an unwanted change in gears; it just >>>>>> sounded like something that shouldn't be happening. >>>>>> >>>>>> Well, this has gone on intermittently since about 2004. Yesterday, >>>>>> however, the chain broke. Broke completely in half, both sides after >>>>>> starting from a standing stop again. Fortunately, I was carrying a >>>>>> spare >>>>>> SRAM Powerlink and the event took place while crossing an intersection >>>>>> near >>>>>> a strip mall that had a bike shop. I borrowed their chain tool to drive >>>>>> out the pins of the broken link and installed the Powerlink and took it >>>>>> easy on the way home, worried that it might happen again. >>>>>> >>>>>> My question is: What the heck gives?? The chain is a SRAM 971 which >>>>>> is designated as the proper chain by the manufacturer for 9-speed >>>>>> cassettes. The cassette is a 9-speed Shimano hyperglide, and the >>>>>> crank/chainrings are Velo Orange Cru. >>>>>> >>>>>> -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/8f49f847-59e0-409c-9de9-6b4f9888b69fn%40googlegroups.com.
